The Physics of Exciton-Polariton Condensates

Konstantinos Lagoudakis obtained a BSc in Physics at the National Kapodistrian University of Athens in 2005 followed by an MSc in Optics and Photonics at Imperial College London in 2006. In 2010 he completed his PhD in Photonics at the Ecole polytechnique fédérale de Lausanne (EPFL) in the Laboratory of Quantum Optoelectronics, where he stayed for another year as a post-doctoral fellow. The outstanding quality of his PhD thesis led to the EPFL Doctorate Award and EPFL Press Distinction. Since 2012, he has been working on on-chip non-classical light sources and developing new technologies for quantum information processing in the Nanoscale and Quantum Photonics Laboratory at Stanford University as the recipient of the Swiss National Foundation advanced researcher fellowship.

INTRODUCTION
From electronics to optoelectronics
From Louis De Broglie to condensation of dilute atomic gases
Condensation and optoelectronics: a dream becomes reality
Overview

CONDENSATION AND EXCITON-POLARITONS
Bosons and condensation
Microcavities
Polaritons
Polariton condensates

EXPERIMENTAL TECHNIQUES AND SAMPLE
Sample
Lasers
Setup
Methods

SYNCHRONIZATION OF POLARITON CONDENSATES
Introduction
Condensation in a synchronized state
Desynchronized condensates
The power dependence of the energy difference
On the pre-existence of the synchronized state
From a simplistic approach to a full model
Conclusions

CONDENSATION IN MULTIPLE MODES
Introduction
The effect of the excitation laser on the condensate spectrum
Preliminary observations
Real space tomography
Momentum space tomography
On the coherence of the individual modes
Theoretical approach
Conclusions

CONVENTIONAL VORTICITY
Introduction
The phase singularity
The density at the vortex core
Theoretical model
Conclusions

UNCONVENTIONAL VORTICITY
Introduction
Phase and density properties of HQVs
Polarization resolved interferometry
Density measurements
Probing the mutual coherence between the two spin components
The effect of the polarization splitting
Conclusions

DYNAMICS OF SPONTANEOUS VORTICES
Introduction
Time integrated vortex observation
Time resolved interferometric measurements.
Theoretical approach
Vortex dynamics at the early stages of condensation
Conclusions

DYNAMICS OF POLARITON CONDENSATES IN DOUBLE WELLS
Introduction
Locating the polariton Josephson junction
Methods for the evaluation of the oscillations
Low excitation regime
High excitation power regime
Spectroscopic analysis
Theoretical approach
Conclusions

CONCLUSIONS AND OUTLOOK